Angular1.5 provides us the new concept - Component, like an improvement for old element-directive one.
It would be nice to have clear distinction between them: when to use what.
There is explanation on official site for cases when we should use directive. But all could be covered by attribute-directive. Is there still place left for element-directive in new applications?
Differences between .component() and .directive()
Angular's Team release the last version for helping developers to migrate to Angular 2.
One of the implementation that helps is the .component() method. In fact in Angular 2 we talk much more about Components instead Directives.
Think about components like a small reusable thing that you can declare one time and share in all your applications.
The new .component() method is really similar the old .directive() but introduce some little differences that helps to adopt best practice. For example the link function is missing and you need to use a controller instead.
In this very helpful article by Aviv Ben-Yosef you can read more about the differences between .component() and .directive().
http://www.codelord.net/2015/12/17/angulars-component-what-is-it-good-for/
When To Use
If you want to migrate to Angular 2, use the .component(). So you can learn a very similar syntax to the new version and migrate very easily.
In short, use directives only when you need to manipulate the DOM elements and in other cases use components.
Yes you can use directive as element if your requirement requires it.
Related
I have seen many articles regarding the changes in Angular2 . But I can't find much advantage in using Angular2. Can some one point out some new things that can be done using Angular2 which can't be done using the previous versions.
I know there are changes like $scope changed to this. I'm not asking for changes. I'm asking for new features that is in Angular2.
The TL;DR Version
Because ES6 is important to pick up, so no need for a custom dependency management system anymore. ES6 and Angular 1 together get ugly fast, as they together introduce a bajillion coding styles :(
Although the library is overall heavier, the architecture it uses (all component based) is a lot faster, lighter, and modular for a scalable application. See http://info.meteor.com/blog/comparing-performance-of-blaze-react-angular-meteor-and-angular-2-with-meteor
You receive (upcoming) Server Side Rendering, which enables fast initial load time and Search Engine Optimization (Yay!) See: https://github.com/angular/universal
You receive WebWorker friendliness, which makes your application able to "multi-task". See: https://github.com/angular/angular/blob/master/modules/angular2/docs/web_workers/web_workers.md
Shadow DOM is not fully inherited by Angular 2 yet, but I'm sure it will be. It has some support right now.
The whole concept of $scope is gone. You receive two way data binding with anything you put in your ES6/TypeScript class, but anything more you need to create a Observable or promise. Unfortunately, you can't just shove anything into the scope, digest, and WALAH! anymore.
And of course, all the cool stuff they mention on their website: https://angular.io/features.html
Hope that helps!
Support for different languages TypeScript, Dart, ES5, ES6.
Change detection is much more effective
Support for isomorphic applications where the same code can run on the server, the browser and a WebWorker in the browser
Moves more work to build time to reduce the time for the initial page load.
Simplified binding syntax
Improved DI
There are also lots of mostly smaller and tiny features that Angular2 doesn't (yet?) support which Angular 1.x does.
I know that polymer is primarily used to create reusable elements, and angular is supposed to be used to create web apps (at least from a "high level" perspective), but I wonder, since you can wrap your own "Screens" as polymer elements, which actually could serve as controllers too, and switch the active page with the iron-pages element (see SPA demo), and you can also use more-routing well... instead of "routing by code", it supports one/two way binding and events, I've actually done some small SPA app like that myself, and so far so good actually! moving on-
Assuming I don't care about having some built-in REST wrapper such as the one provided by Angular (Easy to roll up my own if I use Dart), then in Dart's case:
Could polymer actually be used to create full apps?
Would it have any implications in performance if my whole app is in polymer? by that I mean, every screen is really an element, and so on.
Development speed, maintainability, and experience? (considering the fact that I use Dart which helps a lot in these areas)
Overall, is it a good idea? I'd like to know your opinions.
Any companies/indie devs have done this before? not necessarily with Dart, but with TypeScript/JS as well, although I'm 100% set on Dart.
I think Polymer is quite a good fit for that. I wouldn't necessarily go for "a Polymer element per page" but that might depend on the kind of application you are going to build. Especially in Dart Polymer it's a good start to make the root Element a Polymer element. You can for example keep the navigation and switch only a part of the view instead of the entire page (but that might be what you had in mind anyway)
You can also use dependency injection, which is a strong point of Angular.
The dirty checking might be better in Angular 2 but Angular isn't released yet and Polymer also has plans to improve here.
Simple enough question I think. I see people raving about it but I haven't seen anything on the "why" use it. It doesn't seem to me (from my naïve outside perspective) ng-repeat, if not in that nested layer do ng-repeat inside another. I looks like that it doesn't add functionality that angular doesn't already have—I'm sure I'm wrong—
I see the term "lazy loading" being used with it and it doesn't seem like it's that much easier after seeing there docs. What are some things lodash makes significantly easier in AngularJS specifically that I would make it work adding another lib to my project? And what can you do with it that you cannot with angular out of the box?
They're just not the same, and exist for distinct reasons. I think you already know what AngularJS works for, so about your questions:
What can you do with it that you cannot with angular out of the box?
Well, if you need to deal with several data in structures like arrays, objects or mixed/nested shapes, lodash will save you a lot of time and effort.
Maybe there's a lot of items in collections which should be presented to your client application in some particular way, you would have to write a lot of JS code in Angular controllers or services with out the aid of lodash.
If there's a lot of logic tied to your data structures and/or complex algorithms and coding workflow, go for lodash.
Lodash is a great tool, you can get some intro here and of course, just check out the API reference. You can use it at everywhere, either Angular or any other framework, and of course, also at Node too!
I have an AngularJS 1.3 application that will I suppose eventually move to AngularJS 2.0. I've watched the videos from ng-europe and I understand there are many changes. As I expect development to continue with our AngularJS 1.3 code for the next 12 I would like to hear if anyone has any specific suggestions on preparing for 2.0.
My application is simple in that it creates no directives. In particular I would like to hear any tips on how I should go about creating controllers to get ready for them being very different in 2.0. Should I eliminate all references to scope in my controllers. Should I move everything to services?
I hope for some useful suggestions but of course specific ones so this question does not get closed.
Thanks
I think that so little has specifically been announced yet, and there's so much potential for it to change that it's a hard question to answer, e.g. check out this issue for an example of something quite fundamental that's likely to change since the ng-europe announcement.
Within my team we're trying to take the following approach:
Try not to use $scope (controller-as syntax).
Keep your controllers as light as possible by using directives to encapsulate UI functionality and services to deal with data models / API calls.
Use the new syntax for one-way binding where you don't need two-way binding. One-way binding will be the default for Angular 2.0.
Write some unit tests! It'll be much easier to do some significant refactoring if you have some confidence that your code will still work :).
Not only should that help with the move to 2.0 if / when that happens, but it should help your 1.3 apps too!
I start learning recently polymer.
I want to hear yours opinion if its make sense to use both frameworks polymer and angular together or not and if polymer is really ready for production and what is your choice?
Polymer and Angular Together
Yes, of-course they both can be used independently as well as together. Actually they both are two different things and to serve two different purposes, Though they have some common features to offer.
Please refer to this answer for a detailed explanation. It covers more things and tells about how Polymer & Angular both can be used as part of the same project.
Polymer for Production
With the release of Polymer 1.0, they claim it to be the production ready and as per them they have focussed more on the speed and efficiency this time. As a major change of this release they have replaced the shadow dom with shady dom.
Finger Crossed, I am also intending to use it in my project. Though I have heard very little of it being used in Production by others.
I think Yes, is not a bad choice ! For example i try to use Angular for the little bit complex Service like the Auth Token Authentication, and Polymer for the others ! I want to use Material Design and the right choice is Polymer throught the Paper Element, i tried ngMaterial but is not so good like the Material in Polymer .... so my Answer for the Moment is Yes !